Drive mechanism for guillotine knife bars



F. W. SEYBOLD DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS Aug. 25, 1953 15 Sheets-Sheet 1 Original Filed Aug. 20; 1948 r l N VE N TOR Aug. 25, 1953 F} W.YSEYBIOLD 2,649,910

DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS Originalfiled Aug. 20, 1948 I v I l5 Sheets-Shea"? INVENTOR. I

mflclf w. 65349050 JTTORNEYd' I Aug. 25, 1953 Y F. w. sEYBoLD DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS Original Filed Aug. 20, 1948 l3 Sheets-Sheet 3 ATTORNEY! Aug. 25, 1953 F. W. SEYBOLD DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS Original Filed Aug. 20, I948 13 Sheets-Sheet 4 l NVE N TOR.

BY 2M Aug. 25, 1953 1 w. SEY-BOLD DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS l3 Sheets-Sheet 5 Original Filed Aug. 20, 1948 INVEN'I'OR. ED561653? W JEiVOLD Aug. 25, 1953 (F. w. SEYBOLD 2,649,910

' DRIVE MECHANISM FOR GUILLOTINE KNIFE-BARS Original Filed Au 20, 1948 v Y 1s Sheets-Sheet e INVENTOR. Y

" wwyw 11 TTOR ALE Y8 1953' F. w. SEYBOLD 2,649,910,

DRIVE F OR GUILLOTINE KNIFE BARS Original Filed Aug. 20, 1948 1s sheets-Eben *7 INVENTOR.

Aug. 25, I953 F. w. SEYBOLD DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS- Original Filed Aug. 20,1948

l5 Sheets-Sheet 8 IN'I/EIIV'I'OR. 1 735055 06 WI QEYOLD ATTORNEYJ F. W. SEYBOLD DRIVE MECHANISM FOR GUILLOTINE KNI FE BARS Original Filed Aug. 20, 1948 Aug. 25, 1953 13 Sheets-Sheet 9 M 3 WM my m 7 J Aug. 25,1953 F. w. SEYBOLD 2,649,910 DRIVE MECHANISM FOR GUILLOTINEKNIFEBARS Original Filed Aug. 20, 1948. i 13 Sheets-SheetlO M MM ATTORNEZY Aug. 25, 1953 Fqw. SEYBOLD 2,649,910

DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS I Original Filed Aug. 20, 1948 13 Sheets-She et i1 INVENTOR.

'1 I r gsaagm W al /Bow" ITTORNE m F. -w. SEYBOLD' DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS Aug. 25, 1953 13 Sheets-Sheet 12 Original Filed Aug. 20, 1948 Aug. 25, 1953 F. w. SEYBOLD 2,649,910

' DRIVE MECHANISM FOR GUILLOTINE KNIFE BARS OriginalFiled Aug. 20, 1948 Y 13 Sheets-Sheet 15 I NVE N 'I'OR.

M W WW A TTOR NE Yd Patented Aug. 25, 1953 DRIVE IVIECHANISM FORSGUILLOTINE KNIFE BAR Frederick W. Seybold, Westfield, N. J assignor to E. P. Lawson 00., Inc., New York, N. Y., a corporation of New York Original application August 20, 1948, Serial No.

45,285. Divided and this application'April 5, 1950, Serial No. 154,045

Claims. (01. 164-54) 1 My present invention is a division of my application Serial No. 45,285, filed August 20, 1948, and relates to guillotine type paper cutters and. more particularly to hydraulically operated 2 with a portion of the housing removed showing the driving means for the knife blade and the interconnection of this driving means with the drive for the clamp but omitting portions of the clamping means therefor. 5 clamp driving mechanism.

Essentially y v t n c nt mplat s Figure 7 is a front view of my novel machine necting the knife driving means to the clamp showing the combined drive mechanism for the through a telescoping fluid-filled cylinder and clamp and knife blade. controlling the fluid in the cylinder so that hy- Figure 8 is a schematic fragmentary view taken draulically multiplied clamping force is obtained from the front of my novel mechanism showing during the cutting stroke while nevertheless the the clamp operating elements lifted out of the clamp may be moved down by gravity and withstructure of Figure 7. out hydraulic pressure during necessary opera Figure 9 is a schematic view of the clamp drivtions preceding the cutting stroke. ing elements of Figure 8.

The primary object of my invention is the pro- Figure 10 is a front view of the knife driving elevision of a novel guillotine-type knife and assoments lifted out of the combined view of Figure 7. ciated hydraulically operated clamping mecha- Figure 11 is a schematic view of the elements nism. of Figure 10.

Another object of my invention is the provision Figure 12 is a detailed view in perspective of the of hydraulic clamp operating means whereby a drivefor the knife of my novel cutting machine. telescoping connection between the knife drive Figure 13 is a chart showing the various operamechanism and the clamp is controlled by adtions of my novel hydraulic system. mission of hydraulic fluid under pressure to one Figure 14 is an enlarged front view partly in side or the other of the tube. m transverse vertical section of a portion of Figure 2.

Another object is the provision of a hydraulic Referring first to Figure 6 which is a rear View connection between the knife driving member showing primarily the knife driving elements of and the driven member of the clamp comprising my novel device, the motor I!) through its pulley a closed tube on one of the members with suit- H and belts !2, drives the pulley III which 'is' able posts at each end and a piston slidable in integral with the fly wheel [4: Fly wheel 14 ro the tube and connected to the other member tates freely on the main drive shaft l5 (see also wherein admission of fluid under pressure on one Figure 12) of the machine. The drive shaft [5 side or the other of the piston controls the operais provided with clutch and brake elements as tion of the clamp. well as with overload protective elements of the The foregoing and many other objects of my type shown in my application Serial No. 673,289, invention will become apparent in the following filed May 23, 1946 and now Patent No. 2,570,873; description and drawings in which: The specific clutch and brake elements used, as

Fi ur 1 is a from; i of my .novel paper well as the specific overload protective elements cutter. used, form no part of the present invention and;

Figure 2 is a view corresponding to that of therefore, require no specific description here. Figure 1, with a part of the front broken away in The clutch and brake elements serve, however, order to show a portion of the hydraulic system. to connect flywheel [4 to shaft l5 at the begin- Figure 3 is a schematic representation of the ning of a cycle and to disconnect flywheel l4 hydraulic system of my invention. from shaft l5 at the end of a cycle.

Figure 4 is a cross-sectional view taken from It should be understood, however, that the line 4-4 of Figure 2 looking in the direction of machine is so constructed that it will cycle once the arrows. The vertical section through the in response to a control set by the operator and. hydraulic system in Figure 2 is taken from line will halt until a recycling operation is desired 2-2 of Figure 4 looking in the direction of the so that the knife and clamp will descend once arrows. and rise again for each cycle of operation.

Figure 5 is a cross-sectional view taken from Gear IE on shaft l5 meshes with gear I! (Figure line 55 of Figure 4 looking in the direction 12) on sleeve H50, rotatably mounted on shaft of the arrows. The cross-section line 4-4 in IE, carried in bearing [5| on plate I52. Sleeve Figure 5 indicates the line in which the hori :50 carries gear i53 which meshes with plane- Zontal section of Figure 4 is taken. tary gear I54 mounted on stud its on late I52.

Fi ure 6 is a rear view or my knife mechanism 56 Planetary ar 154 meshes, with internal gear 3 I56 carried by knife drive shaft I8. When shaft I5 is rotated, its gear I6 drives gear I! on sleeve I58, driving gear I53 on sleeve I59 and through gear 154 drives gear I56 on shaft 18 to drive the knife and clamp in the manner. hereinafter dee scribed. Where resistance is encountered by the knife, gear 5 on its stud I55 causes the plate I52 to rotate around sleeve I50 against the compression of spring IN. This operation is also described in my application Serial 'No. 67 i289.

The knife drive shaft I8 carries at the forward end thereof the cranktzll which is pivotally connected at the crank pint! to the knife draw bar 22, the length of which may be made adjustable in any suitable manner, as by the threaded connection at Hi0 (Figure 110).. The upper end of the knife draw bar 22 is pivotally connected by the pin 23 in the clevis 24 at the right end of the knife bar 25 with respect .to Figures 7 and 10. Thus,.-a single rotational cycle ofpit-he knife .drive shaft IS will rotate the crank 20 torpullthe draw bar IZZ-doWn, therefore pullingdown the right-hand end of the knife bar 25, and thenwillraise the bar 22 to force the righthand end of the knife bar up.

. :The opposite end 250i thezknife bar is .simultaneously pulled downby the heavy arm 2.1,the upper end of which is pivotally connected by the eccentric :pin :25 in the clevis 29 at the lefthandr-end of the knife bar with respect to Figures'fl, 10,-.an-d. 11.- Pin 28 (Figure 10) is eccentric and adjustable in knife bar 25 topermit adjustment of arm 21 tocorrespond to the adjustment at H38 at the right side; Gear Eel on 2'8 meshes. with worm 162, carried in bracket I63randh'aving the hexagonal end Eiwhich may berrotated by a wrench to-cause gear I6! and pin 28 to rotate to vary the adjustment.

Arm 21 rotates counterclockwisewith respect to: Figures 7; wand 11 simultaneously with the downward motion of-the-draw bar 22; The arm 2? is then rotated clockwise to raise the lefthand' end 26 ofsthe knife bar 25 simultaneously with the upward or .returnstroke of the-draw bar 22.

unison of motion is achieved by placing an:.a'dditiona-lcrank 35 at the rear end of the knife :drive shaft 15 which is-"keyed to. the shaft I8.a The outer end of crank 35 is pivotally connectedby'crank'pin 36 to the connecting rod 3! which comprises the parallel bars '38 and 39- connectedand'braced'by the :bracing bars i-Iland 4I at' opposite ends. Pin 36 carries the bracing bar 40.??Br'acing bar H at the left side is-carried by the pin 43vvhich is pivotally connected to -the end" oft-the lever 44. never ie is keyed tothe shaft 45" to which in turn the arm 2! isk-eyed. Tfmreforeyrotation: of the knife driving shaft vILB .in addition to rotating crank to pul-ldown thedrawbar 22 also rotates 'crank 35 to pull thezcomposite connecting rod Bl to the right with respect. to Figures -10 and 11.

This results in pulling 'thelower'end of lever M to'athe right and results in counterclockwise rotation of :shaft 45 and corresponding counterclockwiserotation of the-arm .21 with respect to Figures '10. and .11. Therefore, simultaneously with the downward'inotion of draw bar 22, the pin 28 and theleft-handend '26 of the knife bar 25-are drawn downwardly. The counterclockwise rotation of the farm 2'5 causes the knife bars25 to 'swinglaterally totheleft as it is being pulled down, thereby producing the proper transverse motion of the knife bar 25 for efficient cuttingw'hilethe knife driveshaft- Iii-moves through 4 the first half cycle. Further rotation thereof causes the bar 22 to be pushed up, pushing up the right-hand end of the knife bar 25.

At the same time, the passage of crank 35 through .the .second half. ofthe \cycle causes it on continuation of its movement: to push the composite connecting rod 3'! to the left, thereby reversing the operation of shaft 55 and causing it and the arm 2! to rotate in a clockwise directiO'n t0 liftup the left-hand end 26 Of the knife I thuspushed up simultaneously at both ends and swung at the isame time laterally to the right during this rising motion in order to be ready for the next operation.

'The clamp operation is shown in Figures 7, 8 and 9. Arm 44 and the end member 4! of the composite" connecting rod 37 are pivotally connected by pin 43 also to the piston rod 55 of the piston 5 l which 2inturn :is slidable in the cylinder 52. The end of cylinder'52 hasan extension 53 which is pivotally connected at 54 to the arm 551-keyed to 'the1shaft55. .Shaft 56 carries the lever 51 keyed thereto. Lever 5% is pivotallyconnected by=pin-53 to theconnecting link 59. Link 5.9 ispivotally connected by pin 5%) to the bell crankdever 6| which is free to rotate on the shaft 52esecured in the=frame of the machine.

. Theopposite end of lever 5i isconnected by pin 63 to the pulledownlinkte which is pivotally connected at 65 to the .right-handend of clamp 66 v(withrespect to Figures 7, 8Iand 9). The :connection at 65 to theclamp. 66 and the connection at. the opposite. end of .the clamp hereinafter described rnay+take any :form which may be desired such as the adjustable connection described in my aforementioned application Serial No. 673,289.

. The clamp aswell-asthe knife barmay also have the specific construction described in the aforementioned application and may slide in channels and guides of.-the specific shape and formation therein described.- :Suchspecific guide meansand such specific connections require no further description here since they form no part of-the present invention.

:Bell-crank lever GI ha a depending arm Ill and its lower end is connected by pin 1 l to the connecting link Hwhich in turn is connected by pin- I3 to the bell crank 14.. Bell-crank I4 is provided with thebore- 15 which is a loose rotatable fit around the shaft 45. The upperaend I6 .of hell crank I4 is connected by pin H to -the pull down bar l8 which in turn is pivotally connected at 15 to the left-hand end of clamp 66.

When now the knife bar 25 is drawn down so that the connecting rod 31 and the lower end of arm l l are moved to the right with respect to Figures 7,8 and 9, pin 43 is forced to the right, pushing the piston rod 59 to the right with respect to these figures.

Assuming for the-time being that piston rod 59, .piston '5I.,. cylinder 52 and cylinder extension 53 are a single solid unit, the movement of piston'rod-5Il to the right and downward with respect to -.Figure 9 results in corresponding counterclockwise rotation of arm 55 and in corresponding rotation. of shaft 56 and lever 51. Thiscauses the link 59 to rise, thereby rotating the lever 6i counterclockwise to lift the pin 60 thereof-and to lower the pin' 63 thereof. This pulls down the pull bar 64, pulling down the right-hand end of the clamp 66.

The counterclockwise rotation of bell crank lever 6| causes the arm to rotate similarly moving the pin H and. the connecting link 12 to the right and causing the bell crank lever 'I4 16 to rotate counterclockwise, thereby pulling down pin 1?, pull bar 18, and, therefore, pulling down the left-hand end of the clamp 66 together with the right-hand end.

On a reversal of movement of arm 44 so that the lower end thereof moves to the left in the manner previously described in connection with the operation of the knife bar and again treating the hydraulic elements 5lJ5|52-53 as a single solid connection, the operation of arm 55 and lever 51, link 59, lever 6| and pull bar 64 is reversed to raise the right-hand end of clamp 66; the arm 10 has its lower end rotated to the left pushing the connecting link 12 to the left, rotating the bell crank lever I l-16 clockwise and pushing up the pull bar I8 and the left-hand side of the clamp.

Thus, during a single cycle of operation of the knife a lowering of the knife is accompanied by a lowering of the clamp and a raising of the knife is accompanied by a raising of the clamp. The elements are arranged and timed so that the clamp engages the paper surface before the knife enters the paper and leaves the paper surface after the knife has risen above it.

The elements must also be so arranged that the clamp may be caused to descend independently of the knife. That is the principal season why the bell crank lever '|4-|6 is a rotatable fit around the shaft =45 and is not keyed thereto.

Bell crank lever 14-45 may as readily be rotatable on another pivot but for convenience in constructing the mechanism it has been mounted for rotation around shaft 45.

The connection 43505|-52-5354 from the knife operating mechanism to the clamp in order to operate the clamp in synchronism with the operation of the knife is a hydraulic connection as above noted in order to obtain properly controlled clamping pressure and. to permit independent operation of the clamp.

The present structure which includes piston 5| and cylinder 52 in the mechanical path from the knife operating apparatus to the clamp operating means provides a simplified hydraulic method for controlling the clamping pressure. This is accomplished by the valve controls of the hydraulic system shown in Figures 2, 4 and 5, the hydraulic connections shown in Figures 1 and 2, and the hydraulic system generally illustrated schematically in Figure 3, all of which must be taken together with the chart of Figure 13.

Referring first to the schematic view of Figure '3, it will again be seen that arm 44 keyed to shaft 45 is connected by pin 43 to piston rod 56 of the piston 5|, which in turn is slidable in the hydraulic cylinder 52. The opposite end of the cylinder 52 has a connection 53, the right-hand end of which is pivotally connected by the pin 54 to the arm 55 keyed to the shaft 56 which operates the clamping mechanism as previously described.

The operation of the hydraulic system is controlled by valves A|, A2, B and C and their associated conduits and valve seats, all of which are contained in the housing 88 located at the front of the machine. The hydraulic system also includes a reservoir BI and an accumulator 82. The accumulator is provided with a piston 83 biased toward the right by the compression spring 84 6. captured between the left-hand wall of the accumulator and the piston 83. The upper or left-hand end of the piston 5| is provided with the flexible hose X connected to the opening 86 at the upper or left-hand end of cylinder 52.

The lower or right-hand end of cylinder 52 is provided with the flexible hose K connected in any suitable manner to the opening 81 at the lower or right-hand end of cylinder 52.

Flexible hose X is connected to passage L within the valve housing 80 which in turn is connected to valve seat Ll of valve B and valve seat L2 of valve A2. Flexible hose K is connected to a T coupling T2. One outlet of the coupling T2 is connected to passage V in the valve housing 80; the other outlet is connected to conduit U. Conduit U is connected by the T coupling T3 to conduit U| which leads into the right-hand end 90 of the accumulator 85 and to conduit S which in turn is connected to the T coupling T4.

A needle valve G and a check valve D are provided in conduit or pipe U between the T couplings T2 and T3, the check valve being located closer to the coupling T3 and the needle valve G being located between the check valve D and the coupling T2. Passage RI in the valve housing 88 is connected between valve B and the T coupling T4. The remaining opening of the T coupling T4 is connected by pipe R to the threeway valve E so that when valve B is open, the upper opening 86 of cylinder 52 may be connected through elements X, L and L| through valve B and elements RI and T4 to the accumulator 82 and also through element T4 and pipe R to the three-way valve E.

Passage V in valve housing 80 is connected by passage VI to one side of valve AI and when valve AI is opened, the lower opening 81 is connected thereby to passage W| to the pipe W which in turn is connected by the T coupling TI to the pipes Z and Q. Thus, when valve AI is open, the lower opening 8'! of cylinder 52 may be connected by the elements T2, V, VI and valve Al to elements W|, W and T| to both elements Z and Q.

Likewise when valve A2 is open, the upper opening 86 of the cylinder 52 is connected by the elements X, L, L2 and valve A2 and conduit W2 to the pipe W, and also to the coupling TI and hence to pipes Z and Q. An additional conduit or passage V2 in the valve housing 80 is connected from passage V to the valve C and then through pipe N to the check valve F and thence through pipe P to the three-way valve E.

Pipe Z is connected by the T coupling T5 to the pipe Z| which leads to opening 92 at the lefthand end of the reservoir 8|. Coupling T5 is also connected to the pipe Y, the end of which may be provided with a suitable removable closure so that the reservoir 8| may be filled with oil. The reservoir 8| is also provided with a vent 94 through which excess oil or air may escape.

Pipe J connects opening 95 in reservoir 8| with opening 96 at the left-hand end 85 of the accumulator 82. The three-way valve is provided with the three positions I, II, III, indicated in the schematic elements at the right of valve E in Figure 3. Position I connects pipes Q and P and closes off the right-hand end of pipe R. Position II connects pipe R to pipe P and closes off the connection between pipe Q on the one hand and pipes R and P. Position III makes valve E the equivalent of a T coupling in which pipes Q. R and P are connected to each other.

Valve E may be turned to any of the three positionsby-operatingits handle I961 Needle valve G- may. be-a'djus'tedfito the properopening to create the appropriatetpressure diiierential on opposite sides thereof byrotation of handle ltl. Valves A1 andzA2 comprise-a single body :operated together. Valve B is a separate element worked. however, simultaneously. with valves AI and A2. The valve C is independently operable. When the valve element A! is in-the up position, it is closed, while when valve A2 .is in the up position, it is-open; alsoiwhen valve Al is inthe down position it lsopen, and when valve A2 is in the down-positiomit is closed.

, Consequently, whenever valve A i is open, valve AZ-isclosed and vice versa.

Valve B is closed when it is in the up position and is open when it is in the down position. Sincevalves Al, A2 and-Bare moved'up and down simultaneously, valves Al and Beither close or open together and valve A2 is open when valves Al andBare closed andis closed when valves Al and .B are open.

.The check valve Dprevents flow from the accumulator 82 down to the .opening 8'! of cylinder 52 sdthat the hydraulic fluid may only. flow in an upward direction through thepipe U from opening 81 to the coupling'TZ-i. Check valve F permits only a downward flow from pipes P to N, thereby permitting a flow from the reservoir 8! to 'the'opening' 87 at the lower end of cylinder 52 when-valve C is open and valve E is in position I o'rIlI. 1 A pump may, if desired, as shown in Figure 3 be providedbetween reservoir 3! and the pressure side I 12 of accumulator 82 to the'right of piston 83. This will permit the immediate establishment of-pressure in chamber 1 l2 after a shutdown of the machine without the necessity for operating the clamp up and down a few times to create-the pressure.

. I..Foot.treadleoperation to llowertthe clamp The operation of the foot treadle H6 and the operation of the actuating elements for controlling the valves Al, A2, :13 and 'C will be described after 'the'operation of the valves themselves to control the flow of hydraulic fluid and the movement of-the clampare=described.

.As will =be readily understood, the piston 83 under the-pressure of "compression spring 8d createsla predetermined degree of fluid pressure in section 1 l2 of the accumulator between the piston 83 and the right-hand wall 96 thereof. When now the valves-areoperatedaccording to the tabulation shown in Figure 13 so that valve AI is closed-A2 is open, .13 is closed and C is open and the three-way valve is inposition I of Figure 3,-theclamp may be moved down by operation of theioot :treadle H independently of the knife. This is so because thezpiston may move freely with respect. to the lcylinder 5.2 or rather since piston M is held stationary by-its connection to the lever 44 which in turn'is stationary, the cylinder 52 may move down. i This requires that fluid which is forced out through, opening 86 of the cylinder on the downward movement to the right of the cylinder 52 be replaced at an equal rate withfiuid entering the bottom opening 87 of the cylinder 52 so that an equilibrium of pressure is established on' either side of piston 55 during the movement of member 55 in response to movement of the clamp. The clamp '68 descends, therefore, by gravity.

.With valve B closed, the-connection from the accumulator wherein the oil is under pressure through ."pipes Li, L and X to opening 86 at the upper or left-hand end of thecylinder 52 is closed and no oil under pressure'lmay enter at that end. With three-way valve E in the position of Figure 1, 'accumulator pressure oil'can'not pass through couplings TS-andT and pipe R to the bottom opening .81 of the cylinder. Check valve D fprevents any flow down the pipe U from the-accumulator 82 to the opening 81; The opening of valve C permits reservoir oil to flow through elements ZI'T5-ZTlQ-threeway Valve E-elements P-FNCV2-'V and T2 through the hose K to the'opening 81.

Thus, reservoir 'oil may enter the lower or right-hand end of cylinder 52 as the c'ylinder is pulled down by the weight of the clamp 55 to the right with the piston stationary. 'Si-nce valve A2 is open, oil may flow-readily out of opening 86 through elements X-LL2A2W2-W to coupling T! where the fluid from opening 86 mixes with the reservoir oil.

In other words, both openings 86 and S are connected to thereservoir 8l'by opening valves A2 and Cand closing valves Al and B. .Since, however, both connections to the reservoir 8| are through the coupling Tl, a.closed fluid circuit may be regarded as being established from opening 85 through elements XLL2A2-W2- WT l -,-QE-P -FNCV2VT2 and K to opening '81.

Consequently, the pressure on opposite sides of the piston 5| is reservoir pressure or at the very least the pressure is equalized and cylinder 52 may slide readily with respect to the piston 55 even though .the piston is held stationary.

The clamp may, therefore, be brought down by foot treadle.

II.-Hydraulic lifting or return stroke o the clamp When it is desired thereafter to raise the clamp, the hydraulic pressure attained by the compression of spring 84 against piston 83 in the accumulator'is utilized therefor.

For this purpose, valve Al is open, valve A2 is closed, valve B is open and valv C is closed. To accomplish this :result, valves Al, A2 and B are moved down and valve C 'is' moved up. This power returnstroke 'of. the clamp by operating valves A1, A2 and Bdown' and valve C up is used wherether or not the clamp'has been brought down by foot treadle or by power. In other words, the return stroke of theclamp is always a power stroke. Thus, no manual or pedal strength is required to lift the weight of the clamp, and no return spring is required *for the clamp.

In order to use fiuid under pressure to lift the clamp after the cylinder 52 has been moved to .theright with. piston 5| stationary, it is necessary to move the cylinder 52 to the'left while the piston 5| remains stationary. For this purpose, it becomes-necessary to-introduce fluid under. pressure from the accumulator 82 into the opening 86 and as this fluid under pressure causes the left-hand end of the cylinder to move up and to the left, it is necessary simply to permit oil. to drain throughopening 8? from the right-hand lower end of cylinder 52.

The opening of valve Al establishes a connection between the reservoir 8| and opening 8? at the right-hand lower end of cylinder 52 from reservoir 8|, opening 92 and elements ZIT5 ZTIW-WI-AIVIV'T2 and K. Consequently, as the cylinder 52 moves to the left with piston fil-stationary, oil may drain out of thebottom end of the cylinder. The closing of VaNe'AZ cuts ofi the connection between openin 86 at the upper end of the cylinder and the reservoir 8 I. The opening of valve B permits oil under pressure to flow from the compression chamber 2 of the accumulator 52 to the opening 86 at the top of the cylinder over the path U|T3 ST4-R,|-BL|-L-X to opening 86. Valve is closed and in the up position since it is not needed owing to the fact that it is in parallel with valve Al. The check valve D prevents a downward flow from the pressure chamber N2 of the accumulator 82 to the opening 87 of the lower portion of the cylinder 52.

The three-way valve E remains in position I; check valve F has no function since valve C is closed. Therefore, by moving the valves Al, A2, B and C to a position where valves Al A2 and B are down and valve C is up (therefore opening valves Al and B and closing valves A2 and C), oil under pressure is introduced through opening 85 to the upper portion of cylinder 52 to the left and oil bleeds out of the bottom of cylinder 52 through opening 81 to permit this movement to the left; arm 55 is rotated clockwise in the opposite direction from that in which it was operated to lower the clamp, and the clamp is now raised.

As previously pointed out, the mechanism is so arranged that valves AI, A2 and B are driven down and valve C pulled up at the completion of the power cuttin strokes so that the clamp may automatically be raised, or valves Al, A2 and B may be moved down and valve 0 up at the will of the operator after he has moved the clamp down by foot treadle or other manual means in order to raise the clamp once more preliminary to a cutting stroke.

The clamp must be free to be moved down either by power or by foot treadle so that the operator may move the clamp down from time to time without going through a cutting stroke in order-to use the edge of the clamp to determine that the stack of sheets to be cut is lined up properly.

III.Power operation of clamp during cutting stroke The clamp, of course, may also be driven down by a power operation in which case the operation is such that the pressure of the clamp on the sheets is a function of the resistance to oil fiow through needle valve G, producing a clamping pressure. This additional pressure or power may be obtained after the clamp has been lowered so that the clamp may first be lowered by foot treadle and then instead of being raised, the power cutting operating stroke may be started in which case this power cutting operating stroke hydraulically controls the clamping pressure.

In order to use hydraulic power to bring the clamp down or to exert clamping pressure, valves Al, A2, B and C are operated so that Al, A2 and B are moved to the up position, thereby opening valve A2 and closing valves Al and B, and valve 0 is moved down to open. a

It will be obvious that when the clamp is being subjected to a power stroke, the piston 5| is being moved to the right. If the oil or fluid below the piston 5| cannot escape through opening 81, then the mechanical pressure of piston 5| on the oil will drive the right-hand end of cylinder 52 down and to the right thereby rotating arm 55 in a counterclockwise direction or in a direction to operate the clamp down.

'If, in addition, hydraulic fluid under pressure is introduced through opening 81, then the me- 10 chanical pressure of piston 5| is augmented by the introduction of the fluid under pressure through opening 81 to drive the cylinder 52 to the right by a greater distance than would be possible solely by the mechanical operation of piston 5| to the right. At the same time, the fluid in the upper portion of cylinder 52 above the piston 5| must be able to exhaust through opening 85.

The closing of valve Al shuts olT the connection between the reservoir and opening 5? at the bottom end of the cylinder 52 closing off the path reservoir 52 ZI -T5 -Z-T|W W|-A|V|-V-T2K-8'|. The closing of valve B cuts off the connection between the accumulator and the opening 86 at the upper portion of the cylinder 52 by closing the path I |2-- U T3S-T4-R --BL LX-86 Although valve 0 is open, back flow from opening 8'! to the reservoir or the accumulator is prevented by check valve F. Valve A2 is open to connect the top of the cylinder by opening 86 to the reservoir 8| over the path 92Z|--T5-- ZT|-WW2-A2-L2LX85. Oil may now exhaust from the upper end of the cylinder as required by movement of the cylinder 52 to the right.

The check valve D permits the upward fiow from opening 8'! to the accumulator 82 through the path 8l--K-T2-UG--DU-T3U| H2.

Three-way valve E is in the position I of Figure 3; the check valve F has no function since valves 0 and AI are closed.

The needle valve G creates a pressure differential between the hose K and pipe U so that the pressure in the lower section of the cylinder 52 below the piston 5| may be higher than the accumulator pressure in the pressure chamber 2 of accumulator 82. This increased pressure is, of course, achieved by the movement of piston 5| downward and to the right.

The clamping pressure exerted on the clamp is, therefore, much higher than the actual pressure in the accumulator. In the case of a high stack of sheets where increased clamping pressure is desired, the clamp will stop at a higher point and the arm 55 will cease to rotate at an earlier position while the piston 5| Will be pushed fully to the right at every knife stroke since the knife must go through the entire pile.

As the knife drives its Way through the pile, the pressure of piston 5| against the now stationary or almost stationary lower end of cylinder 52 will increase the pressure in the lower end of cylinder 52, thereby increasing clamping pressure in proportion to the additional distance which the knife must go through over that which the clamp must travel through. Therefore, the higher the pile, the greater the clamping pressure achieved.

Check valve D permits the oil to flow upwardly after it has been forced through needle valve G into pipe U back to the accumulator compressing the spring 84, creating a clamping pressure in the cylinder below the piston which is higher than the accumulator pressure owing to the resistance to the flow created by the specific adjustment of needle valve G to the flow of oil in response to the pressure of the piston.

IV .Clamp driven down while the foot treadle is held down During the operation of my novel machine, occasions willfrequently arise Where the operator will desire to bring the clamp down first to the paper stack by means of the foot treadle in order to be sure. that the line-up of the paper is accurate and true; and when he finds that they paper is in the right position,. it is no longer necessary for him to bring the clampup once more to perform the cutting stroke, but he may operate the necessary elementsto perform the cutting stroke In this case, while the clamp is down it is necessary to increase the pressure on the clamp in accordance with the movement of the knife through the stack of paper and also in accordance with the degree of resistance encountered by the knife on its movement into the-stack of. paper.

For this operation, as shown in Figure 13, valves Al, A2 and B are in the up position and valve C is down. Therefore, valve Al is closed, A2 is open, B is closed, Cis open. ;The three-way valve E is in position I of Figure 3.

As was previously. pointed out, the introduction of oil under pressure in the portion of cylinder 52 below the piston 51 or any other increase in pressure thereinwilldrive the-cylinder 52 to theright to rotate the arm 55 in the direction to in.- crease the pressure on the clamp.

At the same time, meansmust be provided to permit oil to exhaust from the portion-of the cylinder. above the piston so that the cylinder may readily move tothe right.

For this purpose, the'closing of valve Al cuts the connection between the reservoir and the bottom of the cylinder closing the path from reservoir 3 I92--Z I-T5-Z-TIWW iA i--- V l V--T2K8l The opening of valve A2 opens an oil passage between the topofthe-cylinder and the reservoir from opening 85 over thepath X L--L2-A2 W2WTIZT5--Z IT2- 'reserv oir 8 i The closing of valve B cuts .off thecon-nect-ion between the accumulator- 82 and. the top of.- the.

Valve C was in the openanddownposition owing to the fact that valves Al, A2, BandC are all in the position in which they were placed by openation of the foot treadle I Hi.

The opening of valve- 0 permitted the reser-;

voir oil, as was previously pointedout,,to move from the reservoir down past-the check valveF: to the hose K and opening 81; in the bottom of;

the cylinder, thereby permitting. the foot treadle to shift the clamp downwardly while; at, theisame time, moving the cylinder 52. to theright and;

down while the piston.5,l remains stationary;

When, however, it is necessary to utilizeoil un. der pressure in the portion of cylinder52 below, and to the right ofv piston 5|, it, is also necessary. to prevent the bleeding off of this excess;pressurev to the reservoir.

For that reason, check-valve F prevents anupr; Ward flow from opening 81 to valve C andpipe 13.,

Since the piston 51 moves; downwardly andtethe right on the power operation of; theknife and.

since the oil cannot escapefrom the portionof. the cylinder below the piston while it may. enter freely from the reservoiraboverthe piston the downward motion of the piston builds up-pressurein the cylinder below the piston, driving the- V.Machine atrestwiththe clamp up In this case, as seenby the notationsin the 52 is stationary at its maximum displacementto theleft.

Reservoir pressure is available to the bottom of the cylinder through reservoir Bl over the path- 92 --.Z: T5 Z Ti-WWl--AiVl--V- T2.-K8l. This pressure differential holds the clamp up.

It will be here-noted that when the clamp is operated-as in column 3 of Figure13 for a. regularpower operation, the. stroke of piston 51 to move the cylinder 52 to the right and,therefore,- rotate arm- 55 in the clampingdirection is such. as to. drive the clamp down ahead oflthe knifeso:

thatthe clamp engages the paper first.

During the return stroke as in-column 2 of Figure :13, the stroke in the opposite direction is soarranged-that the clamp will-leavethe-paper only after theknifehas left the paper pile.

VI.'CZamp:moved -down by the foot treadle without a, power stroke but additional hydraulic power required- In this case, the foot treadle is operated just as in the first operation described for foot treadle operation to closevalves AI and Band open valves A2 and .C. .The. piston. 51 obviously. remains stationary since the knife is not. being operated,

In, orderito obtainthe necessary hydraulic. pressure to move the clamp down by a pressure greater than its own weight would ordinarily produce, it is necessary that fluid under pressure enter the a portion of cylinder 52 below the .piston 5i through openingBFf.

Where the operator desires to work the machine so that the'foot treadle operation will producewthisincreasedpreliminarypressure, the handle wi l o'fthree-way-valve E isadjusted from position Itoposition II of Figure 3. This closes the connection to thereservoir at the'three-wayvalve E-and' connects-the-accumulator to open-- ing 81" at the bottom of cylinder-52 over the following path UI-T3--ST4-'-R-position II of three-way valve- E'P-F-N--CV2V-T2-+' The-opening of va1ve-A2 leaves the opening 86 at the top of the cylinder 52 connected to the reservoir. Thus, the accumulator pressure drives the cylinder down'to drive the clamp down.-

The clamp may bereturned once'more to its upward position by releasing the foot treadle or by going through thepower stroke which then operates by. clamping pressure-since check valve F prevents back flow through valve E to the ac-" cumulator and pressure is obtained by the resistance of needle valve G.

Three-way valve E has the additional position III which connects the accumulator to-the reservoir for relieving thepressure in the accumu-*- lator.

This permits initial filling of the hydraulic. system 'so thatthe entire system may be filled with fluid and permits the fluid to bedrained off where required.

At the time the three-way valve E is opened to position HI for this purpose, the filling opening Y should actually be closed with a sufficiently pressure-tight closure.

Accumulator pressure will then drain backwards over the pathUl-T3S-R position III of three-way valve E-Q--TI--Z--T5-Zl 92 into the reservoir.

If there happens to be more fluid in the system than the reservoir alone can handle, then the excess will exit through the vent 94.

The connection J between openings 95 in the reservoir and 96 in the accumulator permits reservoir oil to enter behind piston 83 of the accumulator as the spring 84 drives the piston 83 to the right, thereby avoiding any vacuum or low pressure which would prevent movement of piston 83 to the right; and when piston 83 is moved to the left during a down power stroke by pressure of fluid past needle valve G and check valve D toward the accumulator, the fluid to the left of piston 83 may bleed off freely back to the reservoir through pipe J, thereby avoiding any back pressure on piston 83.

A small leakage path around the piston 83 may be provided at the mid-position of the piston in the accumulator so that "when, the piston is pushed back close to its ultimate left-hand position, the front face of the piston Will then uncover bleed ports to the path, thereby preventing the building up of a resistance in the accumulator higher than the resistance of valve G.

The handle 200 (Figures 1, 2 and 14) which operates the knife mechanism (and which may be connected thereto in the manner described in the above-mentioned application) also operates the clamping mechanism. Handle 200 is a lever pivotally mounted at 2M on the frame of the machine and having an extension 202 for operating valves A, B and C and an additional extension 203 for locking the same so that twohand operation is necessary.

When handle 200 is pushed down, this motion is resisted by latch 2B4 engaging detent in lever extension 203. Latch 204 is on the end of rod 205 slidable in sleeve 208 and biased toward engagement by spring 206, thereby normally preventing downward movement of handle 200. Bell crank lever 2) is pivotally mounted at 2i I on the frame and is connected at 2l2 to the rod 205. When handle 2 l3, carried by lever 2Ill, is rotated clockwise, lever 2I0 rotates similarly to pull latch 204 out of detent 201, thereby permitting handle 200 to be moved down.

Since both handle 2I3 and handle 200 must be rotated simultaneously, the safety feature of two-hand operation is obtained.

Extension 202 of handle 200 has a pin 2l4 (Figure 14) extending in slot 2|5 of link 2l6 which in turn is pivoted at 2|! to cross bar 2! which operates valves A and B. When handle 200 is pulled down, lifting pin 2l4, pin 214 lifts against ledge 2l5a of slot 2| 5 in link 2| 6 to lift link 2 l 6, cross bar 2 I 8 and valves A and B. Pivot 2|! is connected by link 220 which is connected by lever 22l to link 222 connected to valve C. Consequently, when cross bar H8 is raised, lifting valves A and B, link 222 is pushed down, lowering valve C. l a

At the end of the cutting stroke, abutment 225, carried by lever 21, strikes ledge 228 of link 216, pushing it to the right where portion 2I5b of slot 2l5 registers with the pin 2M, permitting link 216 to fall down and moving valves A and B down and valve C up.

'14 Foot treadle I I0 is essentially a bell crank lever, pivotally mounted at the front of the machine and having an inward extension 230 (Figures 1 and 14) bearing under pin 23l between link 220 and lever Hi to lift link 2 I 6 when the foot treadle H0 is pushed down. i.

In the foregoing I have described my invention in connection with a preferred embodiment thereof. Since many modifications and variations will now be obvious to those skilled in the art, I prefer to be bound not by the specific disclosures herein contained but only by the appended claims.

I claim:

1. In a reciprocating sheet cutting mechanism comprising a vertically reciprocating knife, driving members for the knife comprising a drive shaft, a first crank carried by said drive shaft, a pull bar connected between said first crank and one end of said knife, the invention which comprises a second crank carried by said drive shaft; a second shaft; a third crank carried by said sec-' ond shaft; a link member connecting said second.

crank and said third crank; a fourth crank carried by said second shaft; said fourth crankbeing connected to the other end of the knife; rotation of said drive shaft through a cycle operating said first crank to pull down and push up the pull bar and the first-mentioned end of the knife and operating said fourth crank to pull down and push up the other end of theknife.

2. In a reciprocating sheet cutting mechanism comprising a vertically reciprocating knife, driving members for the knife comprising a drive shaft, a first crank carried by said drive shaft, a pull bar connected between said first crank and one end of said knife, the length of said pull bar being adjustable; the invention which comprises a second crank carried by said drive shaft; a second shaft; a third crank carried by said second shaft; a link member connecting said second crank and said third crank; a fourth crank carried by said second shaft; said fourth crank being connected to the other end of the knife; the point of connection of said fourth crank to said knife being adjustable vertically; rotation of said drive shaft through a cycle operating said first crank to pull down and push up the pull bar and the firstmentioned end of the knife and operating said fourth crank to pull down and push up the other end of the knife.

3. In a reciprocating sheet cutting mechanism comprising a vertically reciprocating knife, driving members for the knife comprising a drive shaft, a first crank carried by said drive shaft, a pull bar connected between said first crank and one end of said knife, the invention which comprises a second crank carried by said drive shaft; a second shaft; a third crank carried by said second shaft; a link member connecting said second crank and said third crank; a fourth crank carried by said second shaft; said fourth crank being connected to the other end of the knife; the connection of said fourth crank to said knife comprising registering openings in said members; a rotatable shaft through said openings; the portion of said shaft through the opening of one of said members being eccentric with respect to its center of rotation; rotation of said drive shaft through a cycle operating said first crank to pull down and push up the pull bar and the first-mentioned end of the knife and operating said fourth crank to pull down and push up the other end of the knife.

4. In a reciprocating sheet cutting mechanism comprising a vertically reciprocating knife, driv- 

